<?php

/**
 * Abstract argument handler for simple formulae.
 *
 * Child classes of this object should implement summary_argument, at least.
 *
 * Definition terms:
 * - formula: The formula to use for this handler.
 *
 * @ingroup views_argument_handlers
 */
class views_handler_argument_formula extends views_handler_argument {

    var $formula = NULL;

    /**
     * Constructor
     */
    function construct() {
        parent::construct();

        if (!empty($this->definition['formula'])) {
            $this->formula = $this->definition['formula'];
        }
    }

    function get_formula() {
        return str_replace('***table***', $this->table_alias, $this->formula);
    }

    /**
     * Build the summary query based on a formula
     */
    function summary_query() {
        $this->ensure_my_table();
        // Now that our table is secure, get our formula.
        $formula = $this->get_formula();

        // Add the field.
        $this->base_alias = $this->name_alias = $this->query->add_field(NULL, $formula, $this->field);
        $this->query->set_count_field(NULL, $formula, $this->field);

        return $this->summary_basics(FALSE);
    }

    /**
     * Build the query based upon the formula
     */
    function query() {
        $this->ensure_my_table();
        // Now that our table is secure, get our formula.
        $formula = $this->get_formula();

        $this->query->add_where(0, "$formula = '%s'", $this->argument);
    }

}
